Jvc Training-2006 Service Manual

TRAINING BOOK

FOR DIGITAL AMPLIFIER RECEIVER RX-D… SERIES

By JSCA ENGINEERING DEPARTMENT JUNE 2006

Second Edit November 2006

CONTENT

• OVERALL

• POWER SUPPLY

• POWER PROTECTION

• DIGITAL AMPLIFIER

• AUDIO DIGITAL PROCESS

• VIDEO DIGITAL PROCESS & HDMI *

• USB WIRE OR WIRELESS**
*

THESE FEATURES APPLY TO RX-D401//402/701/702 ONLY.

**

WIRELESS APPLIES TO RX-D301/302/701/702 ONLY.

OVERALL BLOCK DIAGRAM

Signal Flow and DC Power Supply

*

DVD A. Multi

IN

=DIGITAL SIGNAL

=ANALOG SIGNAL

OVERALL BLOCK DIAGRAM

• A AUDIO means Analog audio, D-OUT means Digital audio output.

• The HDMI outputs video only, even when the HDMI input has both

video & audio data. In the future models, the HDMI will output both A
& V data.

• The digital audio output is not available on models RX-D201/202.

The output format is the same as the digital input signal; other audio
input signals (including HDMI & USB) cannot go through the
DIGITAL OUT.

• The front left & right speaker out audio is applied to headphones.

The CPU will turn off the 7 speaker relays after it detects the
headphone jack is plugged in.

note

• The ‘DVD analog multi channel’ input audio bypasses the DSP

board, and goes into Master Volume Board directly.

• directly.

POWER SUPPLY BLOCK DIAGRAM

‘AMP_+/-B’ switch regulator

POWER SUPPLY 1/5

Regulate
PCB

Master Clock PCB

IC201/301
IC401/801

PWM PCB

CN114-3

D+5V_DSP

Q171

CN114-4

CN530-5

R152 +12V_RY CN530-7

POWER SUPPLY 1/5

• The power supply circuits for 2005 year of RX-D… series are similar. One main

difference is the ‘D+5V_HDMI’ is not in models RX-D201/202/301/302.

• There are two AC power transformers in the unit.

1. T101 for standby power: supplies D+5V and B+5V_Mi DC power for CPU IC501
and RY+9V (power ON/OFF relay circuit).

2. T102 for unit operation after power on: There are more than 15 different DC
voltages provided for unit operation after power is turned on.

• The DC voltages: +B, AMP+B, AMP-B+12V and DCDC_-B+12V all vary (along

with output volume) referenced to ground. The ‘–B’ voltage is -50v~ -62v
referenced to ground. The label ‘DCDC_-B+12V’ DC voltage means this is the
DC voltage supply to the DCDC converter circuit, the +12 DC refers to –B; if
referenced to ground, it is -38v~-50v.

• The +B and AMP+B voltages are higher in models RX-D402/702, because the

output power is higher than RX-D201/202.

note

• The +2.5v, DCDC_+12V, DCDC_-B+12V, AMP-B+12V, D+5V_DSP and

D+5V_HDMI are not produced in the main PCB.

• You could check all of the voltages at the indicated (underlined) locations

without any extension cable, before or after power is turned on. (See the next
page)

• Some additional DC voltages are produced in ‘Regulate PCB’ and ‘Master clock

PCB’.

POWER SUPPLY 2/5

(CN130)

CN114

3. D+5V_DSP

4. D+5V_HDMI

*

The ’D+5V_HDMI’ for models RX-D401/402/702 only.

*

The ‘AMP_+/-B’ switch regulator

composes three sections:

1. MOSFET switch circuit (the important parts are
Q1101/1102, D1107/1108, L1101/1102,
C1117/1118…)

2. Switch driver circuit-IC101.

3. DC-DC Converter Control Board

POWER SUPPLY 3/5

3 2

DC-DC
CONVERTER
CONTROL

AMP_ +/-B

LEVEL

CONTROL

CPU IC501

MOSFET
DRIVE

IC101

SOUND

LEVEL

DETECT

1

MOSFET
SWITCH

Q1101/1102…

7 CHANNEL

POWER

AMP

+

AMP_B

_

AMP_+B

‘AMP_ +/-B’ switch regulator-1a

The CEMF current (via D1107/8) loop
after Q1101/1102 switch off.

+B

POWER SUPPLY 3/5

+12V

-B +12V

IC101

V. feedback

AMP_-B

V.out_det.

-B

POWER SUPPLY 3/5

Tip to measure the outputs of Q1101/1102

POWER SUPPLY 3/5

Waveform (1) at ‘AMP_+/-B’ switch regulator

There is 10v At
Gate higher than
Source for
switches Q1101
on.

AMP+B
(+30V.)

Q1101 on

0 V.

Yellow at G of Q1101 –channel 2

Blue at S of Q1101- channel 1

+B

(+60V.)

1

3

Damped oscillation

2

D1107 on

The waveforms at Source and Gate of Q1101. Three periods in one cycle of

oscillation: 1.Q1101 turned on; 2. D1107 turned on by CEMF; 3. Damped LC
oscillation; Q1101 is switched off during period 2 and 3.

POWER SUPPLY 3/5

Waveform (2) at ‘AMP_+/-B’ switch regulator

About 10v
pulse at Gate of
Q1102 when
switch on

DC 0v line

Blue at D of Q1102- channel 2

Both channel X 10

Both channels are DC coupling

AMP

-B

About

-30v

Yellow at G of Q1102

-B

About

The waveforms at gate and drain of Q1102 after power is turned on.

-63v

POWER SUPPLY 3/5

KNOW THE MOSFET

2SK3599-01MR and IRFB4212 are Enhancement-type N-channel MOSFET

+

• Enhancement-type MOSFET is also known as
normally off (when VGS=O, Drain current=o) MOSFET.

• N-channel MOSFET: The more positive the gate

+

voltage (VGS), the greater the drain current.

-

• There is a built in zener diode in these two kinds
of MOSFET, but it does not show in manual’s
diagram.

• The RDS (resistance between Drain and Source)
will increase when VGS drop to below 8v; and it
causes the MOSFET to get very hot and damage.

• MOSFETs have a thin layer of silicon dioxide;
this insulating layer is kept as thin as possible to
give the gate more control over drain current.
Because the insulating layer is so thin, it is easily
destroyed by excessive gate-source voltage.

• The transient voltages by inductive kickback and other effects may exceed the V

(max)

rating; even handling a MOSFET may deposit enough static charge to exceed the

V

GS (max)

rating.

GS

POWER SUPPLY 3/5

• If the positive drive pulse at Gate is less than 8 volts
(refer to Source), the MOSFET will get very hot to
damage. If the drive pulse is not sharp or is very noise, it
makes MOSFET very hot also.

• If the drive pulse is low & noisy, the drive IC or
peripheral parts may be defective or the power supply
may not be functioning properly.

• When handling the MOSFET, try not to touch the pins
with your fingers.

• It is preferable to use anti-static iron when soldering the
MOSFET.

• When the pair of MOSFETs are damaged, sometimes the
drive IC becomes defective too. Check the drive circuit
before replacing the MOSFETs, to prevent the power
MOSFET from shorting again.

‘AMP_ +/-B’ switch regulator-1b

CEMF charge path

+B 70 V

POWER SUPPLY 3/5

ANP+B 30V

_

(+30 V) *

+

In this circuit it, seems no current through D1107, but D1107 is high power Schottky Diode
with heat sink, If You mean with DC Volt meter but if you use Oscilloscope you can see the

negative peak is clipped. This clipping is by D1107

WHY? *DC METER CHECK

Because there is a large charge current through D1107 that forced by CEMF.

In the relay driver circuit, always has

POWER SUPPLY 3/5

What is CEMF?

a diode parallel with coil,

Counter-Electromotive Force (CEMF) is a voltage developed in an inductor network

by a pulsating current or an alternating current. The voltage's polarity is at every
moment reverse that of the input voltage, therefore opposes the change of main
current flow in the circuit it is called counter-electromotive force (CEMF). The CEMF
is then given by:

Where i is the current, T is time and L is the inductance (L1101) of the circuit. When

the ‘dt’ is very and very small the CEMF (voltage) will become extremely high.

If diode (D1107) is defected it can cause damage to peripheral components

WHY?

(the ‘–’ sign means polarity reverse)

‘AMP_ +/-B’ switch regulator-2

POWER SUPPLY 3/5

IC101-

5

6

Drive IC for Q1101/1102

-B_+12V

DCDC +12V

2

C1122

3
4

1

8

VERAG
DC 42v

+B

AMP+B

AMP-B

-B

7

-B

Audio

CPUPWM

Level

detector

Bootstrap Voltage

1. Capacitor coupling block out the input DC level.

Bootstrap Voltage

The additional
higher positive

USE THE DC CLAMPER

OUTPUT

AVERAGE DC

voltage added to
the low DC voltage

INPUT

AVERAGE

DC 30V

Averag
e

+30v

Averag
e

+0v

0V

2. The DC clamper recovers the DC level at output. *

Averag
e

+30v

29.3V

* In fact it is about +29.3v due to diode forward bias drop.

3. The DC clamper adds DC level to the output.

Averag
e

+42v

42V

+
12v

-

12v

POWER SUPPLY 3/5

•

IC101 is high power MOSFET drive with
independent high and low side reference output
channels.

• The power supply for the high channel drive is
floated.

• The bootstrap voltage from VS to VB through

0.33uF capacitor C1122.

• This causes DC level at pin2-VB to be always
approximately 11v higher than pin 4-VS.

• The UV (under voltage) detector is built in the IC, if
the power supply voltage drops below the threshold
level (about 7.5-8.3 v), The IC stops output.

• If IC101 was shorted, sometimes peripheral
resistors are burnt out also.

About
11v.

POWER SUPPLY 3/5

Waveform (3) at ‘AMP_+/-B’ switch regulator

Yellow at pin 2 of IC101 (R1110)

Blue at S of Q1101- channel 1

DC 0v line

Always about 11v different between pin 2 and pin4 of IC101.

Tip to measure IC101

POWER SUPPLY 3/5

CN115 P-1

DCDC +12V

CN115 PIN4

–B_+12V

CN152 P-4

Vout_DET

CN115 P-5

--B

CN152 P-11

Vout_DET

‘AMP_ +/-B’ switch regulator-3

Q1501­Buffer

POWER SUPPLY 3/5

This feedback
voltage for
regulate the
AMP. +B

Error amp

And ‘V out’ detector

CPU IC501

PIN 62 PIN 65

POWER SUPPLY 3/5

CN151

AMP +/- BPIN 8PIN 7

25VHH
35VHL
42VLL

• The AMP + B voltages vary from about +25v to +42v; depending on the power output of 7

channels at final stage before speaker terminal (The voltages are higher in models
RX-D401/402/702)

• When the audio output level (the analog negative feedback [A NFB] that comes from the

audio final output) is increasing, the DC level at the cathode of diodes D211-D311…
(7 diodes) is increased proportionally.

• This increased DC voltage via buffer Q1501 turns on Q541 first (0.7v), and will turn on

both Q541 and Q542 if the DC level rises higher (2.57v). Then the low state will input to
pins 66 and 90 of IC501 (OUT_LEVEL 1 and OUT_LEVEL 2). This causes IC501 to output
a low state on pins 62 and 65 (V CHANGE_1 and V CHANGE_2) to DCDC CONVERTOR
CONTROL board.

• These low state inputs (through CN151 pin 7 & 8) switch off Q1151, Q1152, and it effects

the DC level at pin 1 of IC111 (error amp). Finally, it changes the PWM pulse’s duty cycle
duration at IC112 pin 1, thus rises the AMP + B voltage to around + 35v ( VCHANG_1
active only) or + 42v (both VCHANGE_ 1 and _2 are active).

• The ‘FEEDBACK‘ from ‘AMP+B’ goes into ERROR AMP IC111 pin 3 through CN151 pin 2,

it is for stabilizing the ‘AMP+B’ regulation.

POWER SUPPLY 4/5

+2.5V regulator built-in the IC supply to
digital circuit inside and outside of IC.

+7V

+2.5V

-2.5V

-7V

Use of the built-in ±2.5V regulated supply to the inside and outside digital
circuits, especially for master clock generation circuit, prevents digital
noise interference to analog GND.

POWER SUPPLY 5/5

Some Other DC Voltages Not In Main PCB

DC +3.3V, +1.8V, +1.2V and TX5V

HDMI

BOARD

1

IN

9V

IC793

OUT

TX5V

5

OUT PIN 18

IN

5V

5V

IC791

OUT

IC792

OUT

1

2

ADJ---------- 1.8V

IN

1

2

ADJ---------- 1.8V

3.3 V

3.3 V

5

DSP

4

BOARD

7

IN

5V

IC692

1

IN

5V

IC691

OUT

3.3 V

5
4

2

ADJ---------- 1.2V

5
4

OUT

APPLY IN
BOARD

3.3V

1

C661
DSP

CN661-3

CN662-3

USB

wireless

IN -3.3V

BOARD CN11

FRONT INPUT

3

BOARD

CN961

IN-

3.3V

3

POWER SUPPLY 5/5 NOTE

• IC791, IC792 and IC691 are same type of regulator IC

and the voltage from ‘output 2’ (pin4 of the IC) can
be adjusted. We see the voltage is 1.2v at pin 4 of
IC691, and others are 1.8v.

• IC793 outputs TX5V to the HDMI out jack, this 5v is

sent to the outside video monitor for HDMI
connection detect; without this 5v, the monitor
cannot accept signals from the HDMI input.

• The +2.5v and -2.5v also are not produced in main

PCB, they are from the PWM PCB; shown on the
previous page.

PROTECTION CICUIT 1/8

FOR MODELS: RX-D201/202/301/302

Where to measure

Not use

7 protect

inputs

(Q212/213 R226 NI)

PROTECTION CICUIT 1/8

• If the power auto shuts off a few seconds after turn

on, most likely it is caused by the power protection
circuit. We describe the protection circuit on models
RX-D201/202. It is similar to other RX-D… series
models and can be used as a reference for
troubleshooting.

• There are 7 protection input pins (only 5 pins used in
these 4 models) on CPU IC501; any of them could

cause the protection circuit to be triggered and shut
down the power. The marked voltages are +5~10%

NOTE

tolerance.

• The underline marked voltages can be measured in
power standby mode; (e.g. 2.01v, 4.83v …) but have
to be checked again once power is on.

PROTECTION CICUIT-SUP. 1

For models RX-D401/402/701/702

These 3 pins are NOT used for

Where to measure

7 protect

inputs

protection input on models

RX-D401/402/701/702

THERMAL For models RX-D401/203/701/702

2.01v

4

Include +7v, DSP D+5V,
D+5V_HDMI DETECTION.

Not use, because Q212,213 and R220 are NI.